1230905 has 16 divisors (see below), whose sum is σ = 1648080. Its totient is φ = 876288.

The previous prime is 1230881. The next prime is 1230907. The reversal of 1230905 is 5090321.

It can be written as a sum of positive squares in 8 ways, for example, as 182329 + 1048576 = 427^2 + 1024^2 .

It is a cyclic number.

It is not a de Polignac number, because 1230905 - 2¹⁸ = 968761 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (1230907) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1559 + ... + 2211.

It is an arithmetic number, because the mean of its divisors is an integer number (103005).

2^1230905 is an apocalyptic number.

It is an amenable number.

1230905 is a deficient number, since it is larger than the sum of its proper divisors (417175).

1230905 is a wasteful number, since it uses less digits than its factorization.

1230905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 700.

The product of its (nonzero) digits is 270, while the sum is 20.

The square root of 1230905 is about 1109.4615811284. The cubic root of 1230905 is about 107.1703984225.

The spelling of 1230905 in words is "one million, two hundred thirty thousand, nine hundred five".